Recording of music and speech



June 24, 1930. H. B. WIER 17 RECORDING OF MUSIC AND SPEECH Filed Aug. 14, 1919 2 SheetLs-She'eg 1 /n 1/6 H f0 flan y 5. l l fer June 24, 1930. H. B. WIER 1,765,517

' RECORDING OF MUSIC AND SPEECH Fi1ed Aug. 14, 1919 ZS heetS-Sheet 2 071497227. Hair/y 5. W/er more particularly musical vibrations.

Patented June 24, 1930 UNITED STATES PATENT OFFICE HARRY B. 'WIE'R, 0E IPLAINFIELD, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK RECORDING OF MUSIC AND SPEECH Application filed August 14, 1919. 'Serial No. 317,410.

This invention relates to phonographic methods of recording sound vibrations, but more particularly to such systems in which tones independently produced by individual musical instruments are blended in a single record.

The object of the invention is to improve the recordation of sound vibrations and It is a further object of the invention to eliminate from the record, distortion ordinarily induced therein by resonance of the various recording instrumentalities. It is also an object'of the invention to ermit the controlor modulation of the effect produced by the sound-producing instrumentalities before recording.

- In accordance with a feature of the invention, the intensity of the vibrations of eachof the instruments of an orchestra or other ensemble, or of a group of instruments, may be modulated at te will of the leader after being produced, without the assistance of the person using the instrument.

In accordance'wlth another feature of the invention, there is also provided means whereby undesirable noises and resonance or any other tendency towards unduly empha: sizing certain frequencies or certain ranges of frequencies, due to any part of the apparatus so associated with the essential vibrat ing parts as to cause an audible effect, are eliminated.

. The method of recording, as described herein, consists in first converting the audible vibrations, produced by musical instruments or otherwise, into electrical vibrations of exactly the same characteristics; modifying such electrical vibrations by suitably increasing or decreasing the intensities of the harmonic components of the electrical wave which are unduly over or under-emphasized by any active part of the vibratory structure or associated parts, and converting such modified electrical vibrations into audible vibrations and recording such modified vibrations.

It has been the practice heretofore to group the various instruments according to their intensities and distribute the players at certain points with reference to a sound.

collector in accordance with the intensity and sound-carrying qualities of, the particular instrument. The number of instruments which can be used at one time is therefore limited and the modulation of each instrument is very difficult and can only be obtained by great care and practice. In ac.-

cordance with the present invention, however, the grouping of the players is an im- .material factor and any number of instru-- an almost perfect record may be obtained.

It is the purpose of the invention to have each of the players in a separate room or compartment from which they may have full view of the leader so that the proper time will be kept. The use of separate compartments for each instrument permits the use of compartments which are accoustically designed and corrected for each instrument.

In the reproduction of phonographic music there is a very noticeable factor called the scratch sound or noise, which tends to detract from the quality of the music. It is noticeable that'this is more pronounced during the silent or non-playing intervals of the record. The vibrations of the stylus during the silent or non-playing interval are not controlled by the impressed vibrations and, due to friction and other causes, it is free to vibrate and cause indentations later reproduced as scratch noises. It is, therefore, necessary to provide means whereby this free vibration of thestylus may be controlled. 'In the present ihvention this has been satisfactorily accomplishedby superimposing a high frequency'tone during recording, which will produce a trace of uniform intensity on the record during the nonplaying intervals. This frequency tqge can compartment fundamental frequency.

then be filtered out by means of an electric wave filter, thereby eliminating the scratch noise and also the superimposed high frequency tone during the silent or non-playing intervals of the record.

The type of electric wave filter which it is preferred to use in connection with this invention is disclosed in a Patent No. 1,227,113, to G. A. Campbell, May 22, 1917, and as it is well known to those skilled in the art, a detailed description of it is not included herein.

A more complete understanding of the invention may be had from the following de scription, taken in conjunction with the accompanying drawings, in which Fig. 1 shows a circuit arrangement for the recording of the sound vibrations of an individual instrument, as well as recording that of a plurality of instruments upon a common record called the master record. Fig. 2 shows the arrangement of the compartments for the various instruments, as well as the leaders stand.

Fig. 1 discloses an embodiment of the invention, in which the dotted rectangle 4 represents one of a number of acoustically corrected chambers, in which the individual players, or other means for producing sound vibrations, is located. A transmitter and collecting device 5 is located in the chamber in such a way as to collect the sound vibrations produced by the instrument, and is electrically connected with the electric wave filter 6 which is adapted to correct for t-IX transmitter, such as described in Patent No. 1,188,053 to H. C. Egerton, June 20, 1916, is adapted to be used for this purpose, but any of the ordinary type of transmitters may be employed. It may at times be desirable to use an electromagnetic transmitter, in which case certain alterations would be required to the circuit with which the same is connected. The variable current set up in the primary circuit 7 by the variation of the resistance in the transmitter, which is in turn caused by the sound .vibrations produced by the musical instrument, is induced into the secondary 8 which forms a part of the filter 6. The filter 6 is for the purpose of modifying the fundamental frequency of the compartment, that is the reaction of the vibrations produced by the musical instrument. The current is then induced into the secondary!) which is a part of the sound collecting device. The filter 11, which is inductively associated with the filter 10 by means of the primary and secondary coils 12 and 13, is for the purpose of modifying the fundamental frequency of the transmitter. The current is again transformed to the secondary 16 which is in circuit with the amplifier 14 of the ordinary vacuum tube type. The provision of an amplifier permits the use of sound-responsive, instruments or transmitters having low initial efficiency. The degree of amplification of the amplifier may be varied by means of a variable resistance 15 which is in the output circuit of the amplifier 14 and which is under the control of the leader. There is also a like resistance associated with each one of the circuits associated with the other individual instruments. The leader is thereby enabled to modulate the intensity of the sound produced by an instrument or group of instruments in the same compartment to any desired volume. A filter 74 is inductively associated with the primary coil 17 which is connected in the plate circuit of the amplifier 14. This filter is adapted to modify the fundamental frequency of the recorder 18. The recorder 18 is inductively associated with the filter 74. An electromagnetic recorder 18, such as described in Patent No. 1,284,623 to H. C. Egerton, is adapted to be used in connection with this invention, but any suitable recorder or means of recording may be employed. In this way the vibrations of the sound wavesof the individual instrument are recorded on the record 19. A means for generating a high frequency current is shown at 20 operatively associated with the secondary of the induction coil 21, which is connected in circuit. with that leading from the individual instrument. This high frequency current is thereby superimposed on the current traversing the circuit of the individual instrument, to cut a uniform trace upon the record including the silent or non-playing intervals.-

The various transmitters associated with the individual instruments are coupled with a common circuit which is represented by the numeral 22 by means of suitable induction coils, the leads 23 and 24 serving to indicatecircuit arrangements similar to that described in connection with the instrument or compartment 4. A filter 25 is inductively connected to the; common circuit 22 for the purpose of filtering out the natural frequency of the reproducing apparatus which is subsequently used in reproducing a master record. A recording means 26 is adapted to record the sound vibrations produced by the combination of the various instruments of the common or master record 27. This record may be included in circuit with the modulating filter 28 and filter 7 5 by means of the key 30. The modulating filter 28 consisting of variable inductance and capacitance is inductively associated with the filter 25. The current in the filter circuit 28 may be varied by means of a variable resistance 29, whereby the volume as a whole may be varied, while the intensity of any portion of the scale may be varied as desired by the leader by varying the inductance or capacitance. The filter 75, which is interposed between the filter 28 and they "electromagnetic recorder. 26, is adapted to filter out or modify the fundamental frequency of the recorder. The loud speaking receivers and sound distributing devices 31 and 32 are also associated with the circuit 28 to audibly'reproduce the vibrations of the combined instruments simultaneously with recording, and may be excluded, if desired, by means of the key 33. The type of receiver preferably employed is shown in Patent No. 1,124,401 to H. C. Egerton, J anuary 12, 191.5, and since it does not form a part of the present invention, a detailed description thereof is not included herein.

A telephone receiver 34 is also inductively associated with the common circuit 22 by means of suitable repeating or induction coils as shown at 35 and 36, whereby the leader ma hear the music produced'by the players w en it is not desirable to use the loud speaking receivers as shown at 31 and 32. He is thereby guided in modulating the Various tones by means of the variable resistances 15 and 29 so that the music when finally reproduced will be of the desired quality.

Various instruments such as violins, cornets, etc., may be collected together in groups, and each of the groups connected to a single circuit whereby the leader may modulate any one of the various groups rather than the particular instrument. In

this way the apparatus that the leader will necessarily have under his control is minimized, and he can thus modulate the intensity thereof to a finer degree.

In Fig. 2 there is shown an arrangement of the compartments or booths which are acoustically arranged to best suit the instru ment adapted to be played therein. The compartments are fitted with a glass-front to enable the player to have a full view of the leader so that the proper time may be kept, The sound collectors 68 are arranged in respective compartments so as toproperly collect the sound vibrations set up by individual instrument. A suitable Fig. 1, is positioned in the sound collector 68 andis electrically connected to its respective circuit by means of the cable 69 which is splicedto the main cable 70. This main cable leads into the cabinet 71 in which is located the apparatusand circuits such as described in connection with Fig. 1, with the exception of variable resistance elements which are positioned in the leaders stand 72 upon which is mounted suitable handles, one of which is indicated at 73 for varying such resistance. These various resistance' elements are connected to the apparatus and circuits located in the cabinet 71 by means of the cable 7 4. The usual recording mechanism is shown on the top of complished in many different ways other than that shown in Fig. 2, without departing from the spirit of the invention.

-The necessary floor space required when separate compartments are employed may, in many cases, not permit the positioning of the compartments so that the players will have full view of the leader. In such cases in which this is not permissible, the compartments may be located in a convenient place out of view of the leader. The leader in such cases may control the playing of the players by means of lights or other signals of different character, that is, by providing lights which will represent the ternpo or time and the intensity desired by the leader.

What is claimed is:

1. The combination of an instrument for producing sound'vibrations, an acoustically corrected chamber for such instrument, an electrical circuit, means for converting said vibrations into electrical vibrations in said circuit, means in said circuit for modifying the vibratory effect of the sound vibrations on said chamber, and means for recording such electrical vibrations.

2. The method of recording sound vibration which consists in converting sound vibrations into electrical vibrations in a plurality of individual electrical circuits, filter ing out the electrical vibrations of undesirable frequencies, collecting the electrical vibrations of the individual circuits at a common point, and recording such electrical vibrations.

3. The method of recording sound vibrations which consists in converting sound vibrations produced by instrumentalities into electrical vibrations in an electrical circuit individual to each instrumentality, modifying the amplitude of the frequency in the neighborhood of the fundamental frequency of the instrumentalities, collecting the electrical vibrations in the individual circuits at a common point, and recording the modified electrical vibrations.

4. A system for recording sound comprising a plurality of instruments for producing sound vibrations, means for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments,

means to filter out the undesirable electrical vibrations in such individual circuits, means for operatively associating said individual circuits with a common circuit, and recording means included in such common circuit.

5. A system for recording sound comprising a plurality of instruments acoustically isolated from each other for producing sound vibrations, means for filtering out any undesirable vibrations produced by an individual instrument, means for collecting the vibrations of the individual instruments at a common point, and means responsive to the collected vibrations to record the combined effect of the individual instruments.

6. A system for recording music comprising a plurality of instruments acoustically isolated from each other for producing musical vibrations, means for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments, means for modifying electrical vibrations having a frequency in the neighborhood of. the fundamental frequency of the converting means, means for collecting the modified vibrations in the individual circuits at a common point, and means responsive to the collected vibrations to record the combined effect of the individual instruments.

7. A system for recording music comprising a musical instrument, an acoustically corrected chamber for such instrument, means for converting the vibrations produced by said instrument into electrical vibrations in an electrical circuit, means included in said circuit to modify vibrations of undesirable frequencies produced by the reaction of said chamber on the vibrations produced by the instrument, and recording means associated with said circuit.

8. A system for recording music comprising a plurality of instruments for producing musical vibrations, means for converting such vibrations into electrical vibrations in electrical circuits individual to each instrument, means for collecting the vibrations of the individual instruments at a common point, means responsive to the collected vibrations to record the combined effect of the individual instruments, and means associated with the circuit individual to each instrument to record the vibrations produced thereby..

9. A system for recording and reproducing music comprising a plurality of instruments for producing musical vibrations,

means for converting such vibrations into electrical vibrations in electrical circuits individual to each instrument, means for collecting the vibrations of the individual instruments at a common point, and means associated with said second mentioned means for simultaneously recording and reproducing the combined effect of the individual instruments. v

10. A system for recording music comprising a plurality of instruments for producing musical vibrations, means for collecting the musical vibrations, a transmitter associated with the collecting, means for converting such vibrations into electrical vibrations in electrical circuits individual to each instrument, means in the individual c1rcu1t for -modifying such vibrations therein having a point, and means responsive to the collected vibrations to record the combined effect of the individual instruments.

11. A system for recording music comprising a plurality of instruments for producing musical vibrations, a transmitter for converting said vibrations into electrical vibrations in electrical circuits individual to each instrument, means including capacitance and inductance of a pre-computed value adapted to modify vibrations having a frequency in the neighborhood of any pronounced fundamental frequencyof the transmitter means for operatively associating said individual circuits with a common circuit, and means associated with said common circuit to record said vibrations on a master record.

12. A system for reproducing music comprising a plurality of instruments for producing musical vibrations, a transmitter for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments, means for operatively associating said individual circuits with a common circuit, means havinga natural fundamental frequency for reconverting such elec trical vibrations into audible vibrations, and means associated with said common circuit and said reconverting means to modify vibrations in said circuit in the neighborhood of the natural fundamental frequency of the reconverting means.

13. A system for'reproducing music comprising a plurality of instruments for producing musical vibrations, a transmitter for converting such vibrations into electrical vibrations in electrical circuits individual to each instrument, means for operatively associating said individual circuits with a common circuit, means having a fundamental frequency forreproducing such. electrical vibrations into audible vibrations, and lumped impedance of a pre-computed Value associated with said common circuit and said reproducing means to modify Vibrations in said circuit in the neighborhood of the fundamental frequency of the reproducing means.

14. A system for recording music comprising a plurality of instruments for producing musical vibrations, a transmitter for converting such vibrations into electrical vibrations in electrical circuits individual to each instrument, means for operatively associating said individual circuit with a common circuit, meansfor recording'such electrical vibration-s on a master record, and means for impressing a high frequency tone on the vibrations in the electrical circuit individual to each of the instruments for operating said recording means to make a uniform tone on the record during the silent or non-playing interval.

15. A system for recording music comprising a plurality of instruments for producing musical vibrations, means .for converting such vibrations into electrical vibrations in electrical circuits individual to each instrument, means for operatively associating the individual circuits witha common circuit, means for modifying vibrations of undesirable frequencies, and means. for recording such modified vibrations.

16. A system for recording music comprising a plurality of instruments for producing musical vibrations, means for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments, means to modulate such electrical vibrations in such individual circuits, means for operatively associating such individual circuit with a common circuit, recording means for recording such electrical vibration on a master record, and recording means inductively associated with the individual circuits to record the electrical vibrations of the individual instruments.

17 A system for recording musiccomprising a plurality of instruments for producing musical v1brations,'means for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments, means to modulate such electrical vibrations, means for operatively associating said individual circuits with a common circuit, means associated with the common circuit to emphasize any of the musical vibrations, and means for recording such modulated vibrations.

18. A system for recording music comprising a plurality of instruments for producing musical vlbrations, means for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments, means to modulate such electrical vibrations, means for operatively 'associating said individual circuits with a common circuit, an electric wave filter having variable capacitance and inductance associated with the common circuit to emphasize any of the musical vibrations, and means for recording such modulated vibrations. 7

19. A system for recording music comprising a plurality of instruments for producing musical vibrations, means for converting such vibrations into electrical vibrations in electrical circuits individual to the instruments, an electric wave filter composed of lumped impedance of a predetermined value associated with suchindividual circuits to filter out any pronounced fundamental frequency of the converting means, means for collecting the vibrations of the individual instrument at a common point, and means electrical vibrations produced by the reaction of the chamber on the vibrations produced by the musical instruments positioned therein, means for collecting the vibrations of the individual instruments at a common point, and means responsive to the collected vibrations to record the combined efiect of the individual instruments.

21. In a system for producing music, the combination of a plurality of musical instruments, means individual to each instrument to convert the vibrations produced thereby into electrical vibrations in corresponding electrical circuits, means for modulating such electrical vibrations, means for impressing the vibrations of a plurality of such circuits on a common circuit, and means included in such common circuit to reproduce the combined effect of such musical.

instruments.

22. In a system for producing music, the combination of a plurality of musical instruments, means for transmitting the vibrations produced thereby to a commonpoint, means at said common point for independently modifying the vibratory effects produced by said instruments, and means for combining said effects into a harmonious whole.

23. In means for recording sound, an electromagnetic recorder operating a stylus, which recorder has one period of vibration relative to its supporting structure, and valve circuits for modifying the effect of the natural period of the recording device.

' 24. In means for recording sound, a detector for converting mechanical vibrations into electrical vibrations, recording mechanism responsive to electrical vibrations, a

current amplifying network electrically contector for converting musical vibrations into electrical vibrations, recording mechanism responsive to electrical vibrations and having the effect of over-emphasizing vibrations at the resonant perlod thereof, a current amplifying network electrically connecting the detector with the recording mechanism, and means associated with said amplifying network for reducing the efl'ect of the vibrations at the resonant period of the recording mechanism in a manner to substantially neutralize the over-emphasizing efl'ect oflthe recording mechanism.

In witness whereof, I hereunto subscribe my name this 11th day of August, A. D.

HARRY B. WIER. 

